A business cash reserve is cash set aside to cover shortfalls without borrowing at short notice. Wheatwell Finance, a small-business funding broker in Twin Falls, ID, explains how to size one from your own fixed outflows, worst deposit shortfall, cash cycle and irregular bills, and how reserves compare with a line of credit or working capital financing.
| Counts as reserve | Cash the business can reach within days without losing value |
|---|---|
| Does not count | Receivables, inventory, unused credit lines |
| Size it from | Fixed outflows, your worst shortfall, cash cycle days, irregular bills |
| Partners review | Recent bank statements and balances |
| Official standard | None; rules of thumb vary |
The short answer
There is no single correct number. You will often see rules of thumb quoted as a number of months of expenses, but no rule fits a contractor waiting on draws, a store carrying stock and a clinic waiting on claims equally well, and none is an official standard. The useful answer comes from your own records: how much cash goes out in a typical month, how far deposits have fallen short in a bad month, and how long your cash is tied up before it comes back. This guide walks through that calculation.
What is a business cash reserve?
A business cash reserve is money set aside to keep the business running when deposits fall short of what has to be paid, without borrowing at short notice. It is kept separate from day-to-day operating cash, in the business's own name.
What is considered cash reserves?
- Counts: cash in business checking or savings accounts beyond the operating balance, and similar holdings the business can reach within days without losing value.
- Does not count: unpaid customer invoices, inventory, equipment, the owner's personal savings, or the unused part of a credit line.
- A grey area: money earmarked for a known bill, such as a quarterly tax payment or an annual insurance premium, is better treated as already spent.
Step 1: List what goes out every month
Add up the payments that arrive whether sales are good or not: rent, payroll including employer taxes, insurance, utilities, software, loan and equipment payments, and the owner's regular draw if the household depends on it. Use actual figures from the last twelve months of bank statements, not a budget.
Leave out costs that rise and fall with sales, such as most stock purchases, because they shrink when sales shrink. What remains is the monthly amount the business must find no matter what.
Step 2: Find your worst shortfall
Go through the last two years month by month and compare deposits with the fixed outflows from Step 1. Note the largest gap and how many months in a row deposits fell short. That history is a better guide than any rule of thumb, because it reflects your customers, your payment terms and your sector.
If you have not been in business for two years, use what you have and add a margin for the months you have not yet seen. The evidence we hold for the Magic Valley does not include month-by-month sector data, so we cannot tell you when a slow period is likely for your industry; your own statements can.
Step 3: Add the cash cycle and the lumpy bills
Two more items belong in the calculation. First, the cash tied up in your operating cycle: a business that waits fifty days between paying for materials and collecting from customers needs more cash on hand than one paid at the till. The cash conversion cycle worksheet shows how to count those days. Second, the irregular bills: quarterly estimated taxes, annual renewals, a large equipment repair you can see coming.
Hypothetical example, for illustration only: a business with fixed outflows of $25,700 a month found that its worst stretch in two years was two months in which deposits fell $11,900 short in total. It also has a quarterly tax payment of about $6,300. Covering the worst shortfall plus the next tax payment points to a reserve of roughly $18,200, before any allowance for growth or a worse year than the last two. The owner, not a formula, decides how much further to go.
Reserves, credit lines and working capital funding
| Cash reserve | Line of credit | Working capital financing | |
|---|---|---|---|
| Available | Immediately, with no approval | If the line is open and in good standing | After a partner reviews and approves a request |
| Cost | The return the cash could earn elsewhere | Interest on what is drawn, plus any fees | The total of payments, set by the partner |
| Risk | Can be spent down | A partner can reduce or close the line, often when conditions worsen | Adds a fixed payment during a difficult period |
They work best together. A reserve handles the first shock without a phone call to anyone. A business line of credit, opened while the business is doing well, can back up the reserve. Working capital financing suits a specific gap with a known end date, and is harder to arrange when the business is already short of cash.
How much money should a business have in reserves before borrowing?
Lending partners usually review recent business bank statements, and low or negative balances, frequent overdrafts and returned payments all weigh against a request. A business that keeps a steady cushion in its account looks lower-risk on paper for the same reason it is lower-risk in practice. Building a reserve before you need funding is therefore not just a safety measure; it is also good preparation for a request.
If the reserve keeps being used up by the same recurring gap, that is a sign the business needs a structural fix, such as different payment terms, a line of credit or different pricing, rather than a bigger buffer.
Building a reserve without starving the business
- Open a separate business savings account so reserve money is not spent by accident.
- Move a fixed percentage of every deposit into it, rather than whatever is left at month-end.
- Set a target from Steps 1 to 3 and a date to reach it.
- Top up after any month in which you draw on it.
- Review the target once a year, or when payroll, rent or debt payments change.
Wheatwell Finance is a broker, not a lender, and this guide is general information rather than financial advice. Other guides cover Idaho registration and the cash cycle.
By Wheatwell Finance · Updated